Well, water was the thing for me for quite awhile and I do have a water bottle with me pretty much at all times. I believe it's important to drink lots of water. However, water has been a bit tame for me lately and I like a lot of things. Well, a lot compared to only water.
I like powder infused water - sort of like adult Kool Aide. No cals, just flavorful water.
I really like sparkling waters and related things.
Iced teas can be pretty great, though I don't drink much of them.
I'm kind of in love with iced coffee and will probably have one in a bit (fully decaf)
I like hot coffee, too.
I don't tend to drink fruit juices very much at all, but I like them on special occasions and prefer fresh squeezed, hands down. I like fresh squeezed orange juice and fresh squeezed carrot juice the best, and fresh squeezed apple juice is very yummy, too, which my sister makes on her farm! I also really like grapefruit and tangerine juice.
I drink *mostly* water all the time, though.
I also like margaritas quite a bit - I just *love* the sweet, sour, and savory all rolled into one

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*goes to make an iced coffee*